机制专业毕业设计英文翻译4

外文翻译

STRATEGIES FOR DEVELOPING DISTRIBUTED

COMPUTING SOLUTIONS FOR INDUSTRIAL

ENVIRONMENTS

Abstract：Manufacturing environments are currently largely isolated from the wider community of general purpose networking and software technologies. This paper explores strategies for developing distributed computing solutions for industrial environments. It offers a case study which introduces emerging cooperating technologies and demonstrates how they can be engineered to bridge between proprietary industrially based networks and component based software technologies such as Active X.

1. Introduction

A Distributed Computer System is a collection of autonomous computers connected through a communications network. The advantages of distributed computing systems offering communications between local and remote processes in automated manufacturing include improved strategic planning, flexibility and configurability.

Potential applications include remote access to data. In particular, suppliers and customers are rarely available on a single site and remote access to production line devices for diagnosis would increase productivity and reduce system downtime.

Concerns about the development of such systems include a lack of management infrastructure to maintain distributed systems and the security of transactions. Additional concerns include maintaining the integrity of the data and, more critically, of the manufacturing process itself.

In considering the development of an open distributed system for manufacturing firstly existing networking technologies are explored, then the client/server paradigm

used in the majority of distributed systems is introduced and a strategy for interconnection proposed.

2. Networking Technologies

2.1 Local Area Networks

Local Area Networking technologies are now widely available, reliable and inexpensive. Manufacturing communications generally adhere to the two

fundamental communications patterns of general networking. The first pattern is called temporal locality of reference and states that if a pair of computers communicate once then they are likely to do so again in the near future and then periodically[1]. The second pattern, physical locality of reference, states that computers are more likely to communicate repeatedly with those close to them. These patterns have driven the development of local area networking technologies which offer suitable communications facilities.

The 1970s and 1980s have seen major developments in this field but the industry has now largely focused its attention on three main topologies: the bus, the star and the ring with the most widely installed user base adopting the Ethernet standard available both as a bus and star. Many manufacturing organizations have been tied in to proprietary communications for their industrial and production data which have been slow to standardise,however there are

an increasing number of products which can bridge from a range of industrial fieldbuses to a standard local area network. A typical network layout is given in Figure 1.

2.2 Wide Area Networks

There is also a requirement to offer remote access to the industrial data, for example to enable a consultant to perform remote diagnosis of production line devices or to monitor the status of a manufacturing process. The most cost effective way of transferring this information is to use the